• Journal of Korea Society of Industrial Information Systems
• /
• v.20 no.1
• /
• pp.57-62
• /
• 2015

Recently, thermography camera have been using for body-temperature monitoring. We report on fabrication of prototype thermography camera using the chalcogenide-glass lens and the camera test by analysis of thermal image. In this work, it was found out that thermography camera discerned body-temperature between 20 and $50^{\circ}C$ with noise equivalent temperature difference(NETD) of 87.7mK. It is confirmed that thermography camera using the chalcogenide-glass lens is applicable to the body-temperature monitoring system.

• Journal of the Korean Ceramic Society
• /
• v.41 no.9
• /
• pp.696-702
• /
• 2004

Lifetime of excited electronic states inside the 4f configuration of rare-earth elements embedded in chalcogenide glasses is very sensitive to medium-range structural changes of the host glasses. We have measured lifetimes of the 1.6$\mu\textrm{m}$ emission originating from Pr$\^$3+/ : ($^3$F$_3$, $^3$F$_4$)\longrightarrow$^3$H$_4$ transition in amorphous chalcogenide samples consisting of Ge, Sb, and Se elements. The measured lifetimes fumed out to have their maximum at the mean coordination number of -2.67, which arises accordingly from structural changes of the host glasses from 2 dimensional layers to 3 dimensional networks. This new finding supports that the so-called topological structure model together with chemically ordered network model is adequate to explain relationship between the emission properties of rare-earth elements and the medium-range structures of amorphous chalcogenide hosts with a large covalent bond nature. Thus, it is validated to predict site distribution and lifetime of rare-earth elements doped in chalcogenide glasses simply based on their mean coordination number.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2009.06a
• /
• pp.675-676
• /
• 2009

• ETRI Journal
• /
• v.31 no.6
• /
• pp.667-674
• /
• 2009

Terahertz time-domain spectroscopy has been used to study the optical and dielectric properties of three chalcogenide glasses: $Ge_{30}As_8Ga_2Se_{60}$, $Ge_{35}Ga_5Se_{60}$, and $Ge_{10}As_{20}S_{70}$. The absorption coefficients ${\alpha}({\nu})$, complex refractive index n(${\nu}$), and complex dielectric constants ${\varepsilon}({\nu})$ were measured in a frequency range from 0.3 THz to 1.5 THz. The measured real refractive indices were fitted using a Sellmeier equation. The results show that the Sellmeier equation fits well with the data throughout the frequency range and imply that the phonon modes of glasses vary with the glass compositions. The theory of far-infrared absorption in amorphous materials is used to analyze the results and to understand the differences in THz absorption among the sample glasses.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2003.07b
• /
• pp.826-829
• /
• 2003

Metal/chalcogenide glass semiconductor(CGS) thin film devices were produced in the vacuum evaporator by the methode of vacuum thermal evaporation. We investigated the influence of the correlations of thickness of metal and CGS upon the concentration of Metal in a CGS thin film. It has shown that M/CGS thin film devices were very sensitive to temperature.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1988.05a
• /
• pp.20-23
• /
• 1988

Effect of light irradiation on evaporated chalcogenide glass films of an As-Se-S-Ge system has been studied. Utiling this characteristics diffraction grating of the amorphous film was obtained. Parameters such as film thickness, composition, and exporsure time influencing the diffraction efficiency were also studied. The maximum value of the diffraction efficiency achieved was 4.6% in an $As_{75}Se_{15}S_{35}-Ge_{10}$ film.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2003.07a
• /
• pp.416-419
• /
• 2003

There is a growing need for a nonvolatile memory technology with faster speed than existing nonvolatile memories. We studied of phase-change according to temperature and voltage in chalcogenide thin film base on $Ge_2Sb_2Te_5$. Searching for Tg(Glass transition temperature) temperature controlled on hotplate with RT quenching. We measure I-V characteristic through out bottom electrode(ITO) and top electrode(Al) between $Ge_2Sb_2Te_5$. And compared with I-V characteristics after impress the variable stress.

• Journal of the Korean Ceramic Society
• /
• v.33 no.4
• /
• pp.425-431
• /
• 1996

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.28 no.4
• /
• pp.257-261
• /
• 2015

In this study, we fabricated a thermoelectric module made of nanoparticles (NPs) and glass fibers investigated its thermoelectric characteristics. P-type HgTe and n-type HgSe NPs synthesized by colloidal method were used as thermoelectric materials and glass fibers were used as spacers between the hot and cold electrodes of the thermoelectric module. In the module, the average Seebeck coefficients of the HgTe and HgSe NPs were 1260 and $-628{\mu}V/K$, respectively. The p-n module generated about a voltage of 11.9 mV and showed a power density of $1.6{\times}10^{-5}{\mu}W/cm^2$ at a temperature difference of 7.5 K.

• Electrical & Electronic Materials
• /
• v.10 no.5
• /
• pp.467-472
• /
• 1997

In this study, we investigated the thickness dependence of thermal bleaching(TB) effect as well as photo-induced scalar phenomena, such as photodrakening(PD) effect and photorefraction(PR) change, in chalcogenide A $s_{40}$ G $e_{10}$S $e_{15}$ $S_{35}$ thin films. We found that when these films were exposed for 15 minutes using blue-pass filtered Hg lamp(~4300$\AA$) after annealing for 30 minutes around the glass transition temperature Tg(20$0^{\circ}C$), the refractive index change ($\Delta$n) was varied up to 0.02~0.46 according to each thickness condition and the optical energy gap ($\Delta$ $E_{op}$ ) was shifted to a longer wavelength of approximately 0.67eV, especially for 1000$\AA$-thickness. Also, the TB PD effects have been understood by the results related to optical absorption characteristics. The TB effect could be estimated as increasing the stabilization of amorphous chalcogenide films since absorption slope of extended regions(U) was not changed by annealing. On the other hand, the PD effect could be understood as due to the enhancement of disorder since U and the slope of Urbachs tail(1/F) around an absorption edge were decreased by exposing.ing.n edge were decreased by exposing.